Nanoscale heat flux between nanoporous materials.

Laboratoire Charles Fabry, Institut d’Optique, CNRS, Université Paris-Sud, Campus Polytechnique, RD 128, Palaiseau Cedex, France.
Optics Express (Impact Factor: 3.53). 09/2011; 19 Suppl 5:A1088-103. DOI: 10.1364/OE.19.0A1088
Source: PubMed

ABSTRACT By combining stochastic electrodynamics and the Maxwell-Garnett description for effective media we study the radiative heat transfer between two nanoporous materials. We show that the heat flux can be significantly enhanced by air inclusions, which we explain by: (a) the presence of additional surface waves that give rise to supplementary channels for heat transfer throughout the gap, (b) an increase in the contribution given by the ordinary surface waves at resonance, (c) and the appearance of frustrated modes over a broad spectral range. We generalize the known expression for the nanoscale heat flux for anisotropic metamaterials.

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